The Provençal peasant, who is pretty quick at observing things that have to do with the land, has a dozen expressions at the very most to denominate indiscriminately the vast world of insects, though he possesses a very rich vocabulary by which to describe plants. This or that bit of weed which one would think was known only to the botanists is to him a familiar object and bears a special name of its own. Now the vegetarian insect is, as a rule, scrupulously faithful to its food-plant, so that, with botany and entomology going hand in hand, the beginner is spared many a hesitation. The plant exploited gives the name of the exploiting insect. Who, for instance, does not know the splendid yellow iris? The green cutlasses of its leaves and its yellow cluster of flowers are mirrored in the brooks. The pretty, green Tree-frog, swelling his throat into a bagpipe, sits and croaks in it at the approach of rain. Come nearer. On its trivalvular capsules, which the heat of June is beginning to ripen, we shall see a curious sight. Here, a restless company of thick-set, rusty-red Weevils are embracing, separating and coming together again. They are working with their beaks and are busy mating. This shall be our subject for to-day. Our current language has not given them a name, but history has inflicted on them the fantastic appellation of Mononychus pseudo-acori, Fab. Literally interpreted and amplified, this means ‘the one-nailed insect of the mock acorus,’ acorus in its turn being derived from α, privative, and κόρη, the pupil of the eye. The grammarian’s scalpel, searching and dissecting the entrails of words, is liable, like the anatomist’s scalpel, to meet with strange adventures. Let us explain this scientific jargon, which at first sight seems utterly meaningless. The plant helpful to those without pupils—that is to say, the weak-sighted—is the acorus, or sweet flag, which the medical science of antiquity prescribed for certain affections of the eyes. Its sword-shaped leaves bear some resemblance to those of the yellow iris. Ours, therefore, is the false acorus, a deceptive image of the famous medicinal plant. As for the one nail, this is explained by the tarsi, the insect’s six fingers, each of which is armed with a single claw instead of the usual two. This strange exception certainly deserved to be pointed out; all the same, any one must prefer Iris-weevil to Mononychus pseudo-acori. Neglecting all pomp and ostentation, the everyday name does not topsy-turvify the mind and makes straight for the insect.